1. Field of the Invention
This invention relates to a construction of releasing a cover of an electric parts storage casing wherein a storage casing body, which contains a number of electric parts arranged therein, and has a projecting portion projecting sidewise therefrom, is entirely covered with a cover from an upper side, the cover has a peripheral wall for surrounding an upper portion of an outer periphery of the body, engagement grooves are formed respectively in opposed side surfaces of the body, engagement projections are formed respectively on those of an inner side surface of the peripheral wall corresponding respectively to the engagement grooves, and the cover can be attached to the body by engaging the engagement projections respectively in the engagement grooves, and can be detached therefrom by disengaging the engagement projections respectively from the engagement grooves. This invention also relates to a construction of releasing a cover of an electric parts storage casing wherein a storage casing body of a substantially rectangular parallelepiped shape, which contains a number of electric parts arranged therein, is entirely covered with a cover from an upper side, the cover has a peripheral wall for surrounding an outer periphery of the body, engagement grooves are formed respectively in opposed side surfaces of the body, engagement projections are formed respectively on those of an inner side surface of the peripheral wall corresponding respectively to the engagement grooves, and the cover can be attached to the body by engaging the engagement projections respectively in the engagement grooves, and can be detached therefrom by disengaging the engagement projections respectively from the engagement grooves.
2. Description of the Related Art
As schematically shown in FIG. 7, an electric parts storage casing includes a cover 103 for covering electric function parts, such as a fuse and a relay, stored in a storage casing body 102 on an electric junction box 101, and engagement portions 102a are formed at side or peripheral walls of the storage casing body 102. The cover 103 has engagement portions 103a corresponding to the engagement portions 102a, respectively, and the cover 103 also has an operating portion 103b through which a force is applied to the cover 103 when removing the cover 103 from the storage casing body 102. FIGS. 8, 9 and 10 are a plan view, a side-elevational view and a cross-sectional view of the cover 103, respectively. FIGS. 11 and 12 are a plan view and a side-elevational view, showing the operation of the cover 103 when the cover 103 is released from the storage casing body 102. When a lifting force F is applied to the operating portion 103b so as to release the cover 103 from the storage casing body 102 (FIG. 12), the side wall of the cover 103, having the operating portion 103b, is flexed in directions of black arrows in FIG. 11, and is bulged to a position indicated by a dots-and-dash line, and as a result the engagement portion 103a is disengaged from the engagement portion 102a of the storage casing body 102.
However, in the cover 103, a large force is required for flexing this cover to the position indicated by the dots-and-dash line in FIG. 11. Therefore, the removal of the cover 103 from the storage casing body 102 can not be effected smoothly.